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E Costa

Publications and source records attributed to E Costa.

At least 739 records · Page 41Linked to original sources
PubMedDate not supplied

Massive ocular hemorrhage resulting in blindness in a patient with the sickle cell trait who developed leptospirosis. Case report.

This case report describes the findings of a 18 year-old black male from Bahia, a Northeastern state in Brazil, with the sickle cell trait, who developed bilateral hyphema and vitreous hemorrhage with blindness in the course of leptospirosis. The patient started to complain of blurred vision four days after the start of fever and muscular pain and approximately twelve hours after the introduction of penicillin. The severity of the leptospirosis in conjunction with sickle cell trait was considered to be the most likely explanation for this ocular complication.

Adolescent↗
PubMedDate not supplied

The association between serum potassium at hospital admission and the case-fatality rate of leptospirosis in men.

Severe leptospirosis affects predominantly males and presents a high susceptibility to hypokalemic acute renal failure. As hypokalemia and hyperkalemia induce severe complications, it is important to evaluate if the initial serum potassium is an independent risk factor for death in leptospirosis. The medical records of 1016 patients hospitalized with the diagnosis of leptospirosis were reviewed. The analysis was restricted to 442, according to the following criteria: male, 18 years or older, information about death or hospital discharge and recorded values of serum potassium, serum creatinine and duration of symptoms at admission. Potassium values lower than 3.5 mEq/L (hypoK), 3.5-5 mEq/L (normoK) and above 5 mEq/L (hyperK) were detected in 180, 245 and 17 patients, respectively. The death rate increased with serum potassium: 11.1% in the hypoK, 14.7% in the normoK and 47.1% in the hyperK group (p = 0.002). In a logistic regression model (normoK as referent), including age, creatinine and duration of symptoms, hypoK was not associated with increased death rate (odds ratio (OR) = 0.80; p > 0.1). On the other hand, hyperK showed a significant association with increased risk of death (OR = 3.95, p = 0.021). In conclusion, in this sample of men with leptospirosis initial serum potassium was positively and independently correlated with the risk of in-hospital death.

Adolescent↗
PubMedDate not supplied

Facial nerve palsy associated with leptospirosis.

This case report describes the findings of a 27-year-old black male from Bahia, Brazil, who developed facial palsy during the convalescence phase of leptospirosis. The patient recovered without neurological sequel. This work calls attention to a possible association between leptospirosis and facial palsy.

Adult↗
PubMedDate not supplied

[Severe forms of leptospirosis: clinical, demographic and environmental aspects].

Characteristics of 1,016 patients hospitalized with leptospirosis in the Hospital Couto Maia, Salvador, BA, Brazil, between 1993 and 1997 are described. Higher pluviometric precipitation was related to an increase in the number of hospitalizations during the following month. Males corresponded to 81.1% (824/1,016) of these; mean age was 35.7+/-15.4 years. Almost 94% (778/829) of the 829 patients with information about race were black or mulatto (mixed race). For ages 18 years or above, almost 93% had not completed high school level. The mean incubation period was estimated as 6.3+/-3.9 days. Average duration of symptoms was 6.1+/-2.4 days. Hemorrhagic events corresponded to 14.3% (145/1,016). The case-fatality rate among 1,009 patients that were not transferred was 14.2% (143/1,009). Renal failure was the attributable cause of death in 76.2% (109/143). The data indicate that leptospirosis is closely related to lower socioeconomic levels, and that higher pluviometric precipitation antecedes the outbreaks.

Adult↗
PubMedDate not supplied

Modulation of phospholipases A2 and C activities against dilauroylphosphorylcholine in mixed monolayers with semisynthetic derivatives of ganglioside and sphingosine.

Most of the semisynthetic ganglioside and sphingosine derivatives studied here decreased the rate as well as the extent of hydrolysis of monomolecular layers of dilauroylphosphorylcholine (dlPC) by both phospholipase A2 (PLA2) and C (PLC). For PLA2, the rate of enzymatic activity was inversely correlated (p < 0.001) with the duration of the latency period of the enzymatic reaction. The correlation between the rate of activity and the latency period was not statistically significant for PLC. The potency to inhibit PLA2 and PLC was not significantly correlated with the presence of specific chemical groups. Also, the inhibitory effect is not correlated to changes of the substrate intermolecular spacing or surface potential caused by the sphingolipids (SLs). Conversely, for PLA2 the variation of the kinetic parameters of the reaction with the molecular polarization vector of the SLs are statistically significant (p < 0.01). The rate of phospholipid degradation by PLA2 decreased, and the lag times tended to become longer, with increasing values of the SLs' polarization vector. The kinetic parameters of the reaction with PLC did not show statistically significant correlation with the polarization vector of the SLs. Our results suggest that the configuration of the electrostatic field across the interface is more important than are formal charges or specific chemical moieties in modulating the activity of PLA2. Inhibition of phospholipase activities of these types by specific SLs or their metabolites may be important as supramolecular regulatory steps at the membrane level of the amplification of lipid-mediated signaling pathways.

Carbohydrate Sequence↗
PubMedDate not supplied

[Brain stem ischemia in a boy with resistance to C activated protein and elevated lipoprotein A].

INTRODUCTION: Activated protein C resistance is the most common hereditary coagulation abnormality. In the majority of cases it results from a point mutation Arg506-->Gln of the factor V gene, and characterized by a poor anticoagulant response to activated protein C. CLINICAL CASE: We report the clinical case of a 6-year-old obese boy, who presented with acute hemiparesis. A cerebral MRI revealed an area of infarction in the left hemiprotuberance. Further investigation identified activated protein C resistance (heterozygosity for factor V Leiden) and elevation in lipoprotein (a). His mother also had factor V Leiden mutation. Prophylaxis with acetylsalicylic acid was instituted with favorable evolution. CONCLUSIONS: This mutation, isolated, is usually asymptomatic, unless other risk factors coexist. Although venous thromboembolism seems to be the main clinical manifestation, recent reports consider that activated protein C resistance is also a risk factor for arterial thrombosis and stroke in children. We reinforce the need for systematic and thorough evaluation of etiology and risk factors in cases of stroke in children.

Activated Protein C Resistance↗
PubMedDate not supplied

[Glucose-6-phosphate dehydrogenase deficiency in 2 girls].

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common erythrocyte enzymopathy, affecting over 400 million people worldwide. Portugal is a low prevalence country, but immigrants from endemic regions are common, particularly in the south of the country. In the present study, we report the laboratory findings observed in two black proband children with low G6PD enzyme activity (23 and 18%). The study also included their first-degree relatives. Both biochemical parameters (enzyme activity, electrophoretic mobility and cytochemical test) and genetic determinations (mutation and haplotype characterisation) were performed.

Base Sequence↗
PubMedDate not supplied

Sequelae of biochemical events following photochemical injury of rat sensory-motor cortex: mechanism of ganglioside protection.

In culture the protracted and abusive stimulation of glutamate (GLU) receptors results in neuronal death through a mechanism involving the persistent translocation of PKC and the destabilization of (Ca2+)i homeostasis [(Ca2+)i HD]. In contrast, intermittent GLU receptor use elicits a coordinated expression of immediate early genes (IEG) acting as nuclear third messenger. Brain ischemia also is known to result in the paroxysmal abusive stimulation of glutamate receptors. The glutamate receptive elements in turn degenerate largely as a function of their inability to control homeostatic Ca2+ due to the irreversible translocation of PKC. In the present study we employed an in vivo model of focal brain ischemia using the photosensitive dye, Rose bengal. With this model we sought to determine the neuroprotective actions of MK-801, a noncompetitive blocker of GLU at the NMDA-sensitive receptor and of the semisynthetic gangliosides LIGA 4 and LIGA 20 which in vitro have been demonstrated to block PKC translocation. Moreover, we sought to establish whether the persistent stimulation of ionotropic glutamate receptors would led to a change in ionotropic glutamate expression in the focal and perifocal area. Importantly, the perifocal area (i. e., the region surrounding the area of primary insult) is a region in which profound cellular reorganization occurs including neuronal death and glial proliferation and is a key region to target various neuroprotective drugs aimed at ameliorating the neurodegeneration following stroke. Receptor abuse dependent antagonists (RADA) drugs such as gangliosides selectively curtail the amplification steps that specifically differentiate signal transduction following physiological receptor use from that following pathological receptor abuse.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

[The identification of multiple thrombophilic risk factors in an infant with cerebrovascular accident].

INTRODUCTION: Neonatal stroke (NNS) incidence appears to be increasing over the last years. This is believed to be a consequence of diagnostic accuracy rather than a real amplification of this entity. Nowadays, NNS incidence is estimated to be 1:4000 full newborns. CASE REPORT: Child with left middle cerebral artery territory infarction in which several thromboembolic risk factors were documented both in the child (neonatal sepsis and factor V Leiden) and his mother (lupus anticoagulant, pre-eclampsy and factor V Leiden). CONCLUSIONS: This case supports the increasing evidence in recent reports that association of multiple prothrombotic risk factors (maternal and foetal) is present in NNS genesis. This way the authors agree that wide prothrombotic study may be of crucial interest in identifying subjacent thrombophilic disease, even when an exogenous risk factor is present.

Child, Preschool↗
PubMedDate not supplied

Cellular and subcellular localization of an octadecaneuropeptide derived from diazepam binding inhibitor: immunohistochemical studies in the rat brain.

Immunocytochemical methods, both light and electron microscopic, were used to identify the cellular and subcellular locations of octadecaneuropeptide-like immunoreactivity (ODN-LI) in rat brains serially sectioned in total. ODN-LI includes a newly discovered family of rat brain neuropeptides that are processing products of a common endogenous neuropeptide precursor, diazepam binding inhibitor (DBI). The members of this neuropeptide family have been shown to displace benzodiazepines and beta carbolines from their specific recognition sites located on the allosteric modulatory centers of GABAA receptors. We have previously examined the distribution of DBI-LI in rat brain. The anti-ODN antiserum used in this study does not cross-react with rat DBI, and thus allows a distinct analysis of ODN-LI as opposed to DBI-LI, in rat brain. Neuronal perikarya with ODN-LI were located in many brain nuclei, such as the pontine n., reticular thalamic n., subgeniculate n., supraoptic n. and suprachiasmatic n., and also in brain areas such as cerebral and cerebellar cortex, hippocampus, inferior colliculus, olfactory bulb and subiculum. In addition to perikaryal labelling, a punctate or diffuse immunostaining with ODN antibodies was detected in many brain regions such as cerebellum, hippocampus, amygdaloid area, olfactory tubercle, some of the deep cerebellar nuclei and some circumventricular organs. At the electron microscopic level ODN-LI was identified in neuronal perikarya, processes and terminals. In the axon terminals, ODN-LI appears to be associated with synaptic vesicles. Whenever ODN-LI was detected within neurons, DBI-LI was also found in identical cells. In addition to neurons, DBI-LI was found in glia or glial-like cells, while ODN-LI was not found in these cells. Our findings are consistent with the hypothesis that ODN may be a neuron-specific processing product of DBI and that ODN-like peptides may act as putative endogenous allosteric modulators of various GABAA receptor subtypes.

Animals↗
PubMedDate not supplied

Excitatory amino acid signal transduction in cerebellar cell cultures.

In primary cultures of cerebellar granule cells excitatory amino acid recognition sites are coupled with the stimulation of inositol phospholipid (PI) hydrolysis, cGMP formation and 45Ca2+ uptake. Mg2+, 2-amino-5-phosphonovalerate (APV) and phencyclidine (PCP) potently inhibit signal transduction in response to N-methyl-D-aspartate (NMDA), glutamate (GLU) and aspartate (ASP). Activation by quisqualate (QUIS) is transduced selectively into stimulation of PI hydrolysis and this response is not sensitive to inhibition by Mg2+, APV and PCP. Activation by kainate (KA) is transduced into potent stimulation of cGMP formation and 45Ca2+ uptake. Transduction of KA signal is not affected by Mg2+ and is relatively insensitive to PCP and APV.

Amino Acids↗
PubMedDate not supplied

[A procedure for improving the stability of the total mandibular prosthesis with the aid of the muscular factor in the marked atrophies of the mandibular crest].

The study aimed to define factors involved in improving the stability of total mandibular prostheses by the use in optimal conditions of the muscular factor. This is achieved with a special method for casting of the neutral space which allows to prepare the external surface and to place the artificial dental arc according to objective functional criteria. In the first part of the study notions are discussed related to the practical solution of the problem, such as: the anatomo-functional study of formations which define the neutral space, aspects of the neutral space in the total edentate, and the conformation of total prostheses, as well as the placing of the artificial dental arcs in relation to the neutral space. In the second part a method is presented, for making prints, that was used in 35 cases. The results of the prosthetic procedures, verified clinically and electromyographically are promising.

Bone Resorption↗